This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2001-193417, filed Jun. 26, 2001, the entire contents of which are incorporated by reference.
1. Field of the Invention
This invention relates to an IC card, such as an SD (Secure Digital) card, used, for example, inserted in a card slot, and an electronic apparatus capable of inserting the IC card therein.
2. Description of the Related Art
In electronic apparatuses such as portable computers or PDAs (Personal Digital Assistants), IC cards based on PCMCIA are widely used as memory- or IO-expanding means. Recently, IC cards of this type have come to use a radio communication function such as Bluetooth (trademark) that enables radio data transmission between a plurality of electronic apparatuses.
An IC card having such a radio communication function is provided with a radio interface circuit or a card case housing an antenna. The card case comprises a first portion to be inserted into the card slot of a portable electronic apparatus, and a second portion outwardly projecting from the card slot when the card is inserted. The antenna for radio communication is housed in the second portion of the card case. Accordingly, when the IC card is inserted in the card slot, the antenna outwardly projects from the card slot. In this state, the radio transmission performance of the IC card can be maintained at a high level.
In the above-described conventional IC cards, since the second portion of the card case outwardly projects from the electronic apparatus, it is possible that a user may unintentionally press the second portion, or may place something on it. Thus, the application of an unintentional bending force to the second portion cannot be avoided.
Further, in the conventional IC cards, an electronic component such as an IC chip is housed in the card case. This electronic component is covered with a packaging resin more flexible than the card case.
In the above-described conventional structure, if a bending force is exerted on the IC card from the outside, the packaging resin is elastically deformed in accordance with the deformation of the card case, thereby absorbing the bending force applied to the electronic component. The packaging resin is more flexible and has a lower elasticity modulus than the card case. Therefore, even if the boundary between the packaging resin and electronic component is deformed in accordance with the deformation of the card case, the stress due to the deformation can be suppressed. As a result, the electronic component can be protected by the card case and packaging resin. Therefore, even if a bending force is exerted on the IC card, the electronic component will not immediately be damaged.
As described above, in the prior art, the bending force applied to the IC card is absorbed in the interior of the card case. However, if a strong bending force, which exceeds the stiffness of the card case, is exerted on the second portion of the IC card, the card case itself will be inevitably damaged. In this case, the interior of the IC card will be also damaged, i.e., the electronic component and antenna will be damaged.
It is an object of the invention to provide an IC card of high bendability, which can immediately absorb an external force, such as a strong bending force, when it is exerted on its second portion.
It is another object of the invention to provide an electronic apparatus using the IC card.
To attain the objects, there is provided an IC card comprising: a first portion to be inserted into a card slot; and a second portion outwardly projecting from the card slot when the first portion is inserted in the card slot. The first and second portions are coupled to each other by a bendable coupling.
In this structure, when the IC card is inserted in the card slot, the second portion projects to the outside of the card slot. If an external force is exerted on the second portion to, for example, bend it, the coupling is bent in accordance with the direction in which the external force is exerted. As a result of the bending of the coupling, the external force exerted on the second portion is absorbed. Thus, the stress that occurs in the IC card because of the external force can be reduced, and the IC card can be prevented from being damaged.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.